FIG. 1 is a block diagram of a known telephone call handling system that uses speech recognition. When a call is placed from a telephone 10, a telephony signal is routed through a communication switch 20. The communication switch 20, such as a switch in the Public Switched Telephone Network (PSTN), can route the telephony signal to a communication network service provider operator platform 30. In this case, a telephone operator can interact with the caller, such as to determine if the caller has a question about a telephone bill or needs directory assistance. Once the purpose of the call is determined, the operator can route the telephony signal as appropriate.
Having a live operator interact with callers can be expensive for the network service provider. Therefore, the service provider may instead route the telephony signal to an intelligent Voice Recognition Call Processing (VRCP) adjunct 100. As used herein, an "adjunct" is a device that responds to a request for service processing in a communication network. As shown in FIG. 1, the VRCP adjunct 100 receives the telephony signal through a communication link, such as a PSTN digital T-1 connection, using media processing circuit boards.
An application infrastructure in the VRCP adjunct 100 automatically determines the purpose of the telephone call, such as by using speech recognition, and re-routes the telephony signal as required. If the VRCP adjunct 100 cannot determine the purpose of a particular call, the signal can be re-routed to the operator platform 30. The Conversant Version 5.0 Personal Computer (PC) based system available from Lucent Technologies is an example of such a VRCP adjunct 100.
A basic adjunct may simply respond to touch tone keypad signals, such as Dual-Tone Multi-Frequency (DTMF) signals, selected by the caller. For example, the adjunct may play the following message to a caller: "press `1` if you have a billing question and press `2`for directory assistance." The adjunct would then re-route the telephony signal based on the received DTMF signal.
The VRCP adjunct 100 shown in FIG. 1 also has a limited amount of speech recognition capability. For example, the VRCP adjunct 100 may play the following message: "say the word `one` if you have a billing question and say the word `two` for directory assistance." The VRCP adjunct 100 can then re-route the telephony signal if a "key word," such as the word "one" or "two," is recognized in the received speech signal. If the VRCP adjunct 100 does not recognize the received speech signal as being a key word, the telephony signal can be re-routed to the operator platform 30. A live operator will then determine the purpose of the telephone call.
If the speech recognition capabilities of the VRCP adjunct 100 could be enhanced, such as by recognizing a larger number of key words or by recognizing commonly used phrases, the amount of operator time spent determining the purpose of telephone calls would be further reduced. The How May I Help You (HMIHY) system developed by AT&T is an example of a system with enhanced speech recognition capabilities.
There are a number of problems, however, with providing enhanced speech recognition capabilities in a communication network. For example, a number of VRCP adjuncts with limited capabilities may already be installed in the network. The hardware and/or software used in these existing, limited capability, VRCP adjuncts may be insufficient to support the more advanced processing techniques required by the enhanced speech recognition system, and it may be difficult to update the hardware used by a limited capability VRCP adjunct to provide enhanced speech recognition capabilities. For example, replacing and retesting existing limited capability VRCP adjuncts could be an expensive and time consuming task. Similarly, updating the software used by a limited capability VRCP may be prohibitively difficult.
In view of the foregoing, it can be appreciated that a substantial need exists for a method and apparatus that uses a limited capability VRCP adjunct to provide enhanced speech recognition capabilities in a communication network, and solves the other problems discussed above.